Similar Plan here, Dave
Dave,
I've got a similar plan to start commuting with my iZip E3 Dash here in Seattle. My route is from Ballard to Sodo and is just at 10 miles each way.
I used to commute via normal bike, back in the day, and learned many very important and valuable lessons on how to ride in City traffic.
Number ONE - ALWAYS ASSUME THEY WILL TURN IN FRONT OF YOU, PULL OUT IN FRONT OF YOU AND OPEN THEIR DOOR IN FRONT OF YOU!!!!!!!!! - I don't care if you're lit up like the National Christmas Tree, "THEY CANNOT SEE YOU!!!!
Fortunately, my route now is 70% residential street and bike path, which is fantastic. The only traffic exposure is about 2 miles near the waterfront and should be manageable.
The great thing about the Electric assist is that I can maintain a 20+ pace using assist level 3 and pretty much stay up with traffic in that one area.
As far as shower facilities, we are usually cool enough here in Seattle at 6:30 am that it really doesn't present a huge issue. Unless I decide to totally go animal my arrival is not precipitated with excessive perspiration.
Best of luck with your plan. Let's post here from time to time to see how we are progressing.
John